Seo Minwoo of K-pop boyband 100% has died aged 33. The Korean singer, who performed as Minwoo, was found without a pulse at his home in Seoul on the evening of 25 March, and was pronounced dead by first responders. The cause of death is reportedly cardiac arrest.

The band’s label, Top Media, paid tribute to the artist on its website: “His family, the 100% members, and the Top Media artists and staff members are all grief-stricken and in mourning from the unexpected, sad news.” Minwoo’s family have requested a private funeral.

His former bandmate Woo Changbum paid tribute to Minwoo in an Instagram post, captioning a photo of them together (translated from Korean): “May the souls of the deceased refrain. I hope you are comfortable in the sky. I want you to be a bright star and shine this world.” One fan paid tribute to Minwoo’s support for LGBTQ rights.

The boyband 100% debuted in 2012 as a seven-piece in the K-pop genre, a highly visual form of Korean pop that incorporates elements of western music. The group were the second boyband created by Andy Lee of the K-pop group Shinhwa. They also have a smaller group comprising members of the main band – called 100% V – of which Minwoo was not a member.

Minwoo was the band’s lead vocalist, but took a sabbatical from the band to complete mandatory military service in 2014. Minwoo had also worked as an actor, appearing in dramas such as Sharp 3 and The King and I, and making cameos in the TV series New Tales of Gisaeng and movies including Where Are You Going?

100% had made their Japanese debut in January 2017, breaking through with this year’s Top 10 single Song for You, released last month. They are due to perform in Tokyo and Osaka at the end of April. Top Media has not confirmed if the shows will go ahead.